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What should i do if i find a rabbit with myxomatosis?

4 Answer(s) Available
Answer # 1 #

Myxomatosis is caused by the myxoma virus, a kind of pox virus that only affects rabbits. There are also different strains of this virus that vary in their virulence. Both wild and domesticated rabbits can get myxomatosis. Wild rabbits can survive as carriers, but the disease is usually fatal in domestic breeds (particularly those of European descent). The onset of illness is rapid after transmission, and rabbits typically die within two days of showing symptoms.

Rabbits that contract myxomatosis may suddenly become very ill. If a rabbit is showing symptoms, it is not uncommon for the animal to die within 48 hours.

Within hours or days of contracting the myxoma virus, rabbits will show signs of feeling unwell, such as food refusal or lethargy, and their eyes will become inflamed. If a rabbit does not die within two days, as is usually the case, the illness may begin to affect the mucous membranes and other tissues, including the eyes, nose, mouth, genital and anal areas, and ears (which become droopy if they are usually standing). The rabbit's entire face may also become very swollen, and thick pus may be discharged from the nose. Due to the swelling and discharge, the rabbit will start to have difficulty breathing. Most rabbits die within 14 days of the onset of these symptoms.

In more chronic cases (depending on the virus strain and immunity of the rabbit), lumps and nodules (myxomas) may develop on the body. Rabbits with this lumpy form of myxomatosis may survive and become immune to the myxomatosis virus. This is commonly seen in wild cottontail rabbits but unfortunately seems to be a less likely course of the disease in domestic rabbits. Instead, most pet rabbits that are diagnosed with myxomatosis end up suffering from the acute forms of the disease and eventually die.

This pox virus is spread by blood-sucking insects but can rarely be transmitted through contact with an infected rabbit. Carriers of the virus include:

Diagnosing myxomatosis in a live rabbit is based on a veterinarian's recognition of the classic symptoms, blood and urine tests to detect the virus, and biopsies of myxomas. But, since the disease is so rapidly fatal in most cases, a diagnosis is more frequently made by a postmortem examination.

There is, unfortunately, no specific treatment for myxomatosis so only supportive care (fluids, antibiotics to prevent secondary infections, and pain medication) can be offered by your vet. Because domestic rabbits tend to be very susceptible to the virus and suffer greatly with symptoms of the disease, euthanasia is often recommended. In some cases, however, palliative care can allow a previously young, healthy rabbit to recover.

Unfortunately, the prognosis for a rabbit with myxomatosis is grim. Few domestic rabbits survive this disease.

To help prevent myxomatosis, make sure your rabbit is not exposed to sources of the disease by taking the following precautions:

The myxomatosis vaccine is not available in the United States or Australia; one reason for this a concern that the virus in the vaccine might spread to the wild rabbit population. If this occurred, the wild rabbit population could develop an immunity to myxomatosis, leading to an explosion in the rabbit population. Myxomatosis was at one point deliberately introduced into the rabbit population in Australia to reduce the rabbit numbers; the outcome was an increased immunity to the disease and, in the long run, an increase in the rabbit population.

Ryan iljodbs
Answer # 2 #

You should try to confine any wild rabbit that looks like it has myxomatosis and take it to the nearest vet. Wear gloves and wash hands thoroughly after touching the rabbit. If you are unable to take the rabbit to the vet, report the animal to the RSPCA.

Sepideh Pham
Immunology Nursing
Answer # 3 #

Myxomatosis is a deadly virus. Wild rabbits can carry Myxomatosis, but do not become sick. Myxomatosis is fatal to domestic (pet) rabbits with a 99% mortality rate, and there is no treatment and no vaccine in the USA. Symptoms include swollen eyelids, lips, and genitals, a high fever, lethargy, and progresses to difficulty breathing, and death, within 2 weeks. Myxomatosis is endemic to many coastal areas on the west coast of the USA.

Myxomatosis is a viral infection in rabbits caused by a member of the Poxvirus family. It is deadly to rabbits: the mortality rate has been reported at 99%. It is spread by vectors (mosquitoes and fleas) that have bitten an infected rabbit. Direct contact with an infected rabbit can also spread the disease.

The Myxomatosis virus was introduced into Australia in 1950 to reduce the population of wild rabbits. It got out of control and affected domestic rabbits and spread into other countries. Millions of rabbits have died from it. In the United States there have been an increasing number of cases over the years, especially in The San Francisco Bay Region.

Mosquitoes, fleas, black flies, or fur mites bite a wild rabbit with Myxomatosis and then bite a domestic rabbit. Myxomatosis can also be spread by direct contact between infected rabbits, or indirect contact through handling a sick rabbit, then handling a healthy rabbit.

Myxomatosis cases in pet rabbits are reported in the coastal areas of Oregon, California, Washington, and Baja California, Mexico, in the territory of the brush rabbit (Sylvilagus bachmani), which is a reservoir of this disease.

So far, cases have been reported June-October and January-February (no reported cases yet in November/December or March/April/May).

2021 was the first time we saw myxomatosis in San Jose. Before that it was mostly limited to the coast and mountains. The disease tends to have a seasonal component, starting mid to late summer and going through November.

7/5/22: Los Altos Hills

8/5/22: Mountain View

9/6/22: Boulder Creek

9/27/22: Ben Lomond

10/19/22: Cupertino

11/6/22: Los Altos

8/13/21: 6 year old Male neutered N lop, Los Gatos

8/16/21: 6 month old Male rabbit, San Jose

9/21/21: 1 year old Male Neutered rabbit, Santa Cruz

11/15/21: 6 month old Female Spayed rabbit, Santa Cruz

There have been multiple detections (both clinical suspect and confirmed) of Myxomatosis throughout western Oregon in 2022:

7/27/2022 – Yamhill County8/2/2022 – Yamhill County8/8/2022 – Lane County8/19/2022 – Douglas County8/26/2022 – Lane County9/1/2022 – Washington County9/2/2022 – Lane County9/8/2022 – Washington County

House Rabbit Society is collecting reports of cases of Myxomatosis to add to this list.  If you are a vet with a patient with Myxomatosis, or a rabbit guardian whose rabbit has been diagnosed with Myxomatosis, please email us at [email protected] to have the case added.

If you are a vet in California, please submit deceased rabbits suspected of Myxomatosis for necropsy with a CAHFS state lab (fee $135) or report confirmed Myxomatosis cases to the California Department of Food and Agriculture (CDFA): [email protected].

There have been no recent cases of Myxomatosis reported to the Washington State Department of Agriculture from 2011-2022.

Symptoms may include swelling of the ears, nose, mouth and genitals, conjunctivitis, not eating, lethargy, loss of appetite, fever and lesions.

Myxo is diagnosis by observing the symptoms and biopsies of the lesions. In many cases the diagnosis is made post-mortem, because of the sudden death.

Call your rabbit vet straightaway and quarantine your rabbit from all other rabbits.

What is the treatment for Myxomatosis?Currently there is no effective treatment for Myxo in the United States. Most rabbits die of hemorrhage and or seizures within 10 days. Pain medication and sub-q fluids will make a rabbit more comfortable.

There are vaccines in other countries, but the strains of Myxo can be different therefore a vaccine that works in one area may not in another. We are still looking into this for further information.

Take your rabbit to the vet immediately if you are concerned your rabbit might have Myxomatosis, and separate them from any other rabbits in your home.  Your vet can determine whether your rabbit might instead have rabbit syphilis, an upper respiratory infection, or an eye infection, all of which are treatable conditions.

House your rabbits indoors with window screens.  Rabbits live longer, healthier lives when indoors. Because myxomatosis is just one of many concerns facing rabbits who live outdoors, House Rabbit Society recommends indoor homes for rabbits as the primary preventative, along with screens on doors and windows.

If you live in an area with reported Myxomatosis cases, treat your rabbits monthly with Revolution, to prevent fleas and fur mites.  Revolution is a prescription medication, available through your veterinarian.  Or, treat with over-the-counter Advantage, which provides protection from fleas (but not from mosquitoes or fur mites). Be sure to give your cats and dogs flea treatment, too. Don’t let your rabbit play outside if you live in an area with currently reported Myxomatosis cases.

Vectra 3D is a flea/tick/mosquito/mite/fly/lice repellent for dogs – using it on a rabbit is “off-label” use and could be harmful to your rabbit at the wrong dose. Santa Barbara rescue Bunnies Urgently Needing Shelter uses this medication as just one of their tools to try to keep rabbits safe. Please consult with your vet before using and get bunny-sized dose information from them.

For rabbits who must live or spend some of their time outside, protection against mosquitoes is next best bet, protecting the rabbit’s play area with mosquito netting or some other barrier. Read more on the hazards facing outdoor rabbits.

The Myxomatosis vaccine available in Europe and in the UK has not been approved by the USDA’s Animal and Plant Health Inspection Service’s (APHIS) Center for Veterinary Biologics. There is no vaccine available in the United States, and it is not legal to import the vaccine from other countries.

Hilary Stern, DVM of Santa Cruz, CA has repeatedly tried to import the European vaccine and failed. Dr. Stern said, “The FDA won’t allow it because it is a live vaccine. I am not aware of any killed vaccines that are effective.“

The European vaccine is for a different strain of Myxomatosis. The California (US) strain of Myxomatosis is more virulent, and it is unknown if the European vaccine would be effective against the CA strain.

Santa Cruz County: August2013

Sonoma County: October (Sebastopol – reported by guardian & Dr. Pfann, Brandner Vet)2012

Monterey County (reported by AFRP’s Rescue Rabbits Rock)

Southern California2019 Ventura County: July (reported by CDFA)2017 Ventura County: August (reported by CDFA)2010 San Gabriel Valley (near Los Angeles): July

2016 Marion County: August Douglas County: July-August

2015 Polk County: June2010 Western Oregon2004 Linn & Benton counties: July2003 Linn & Benton counties: July

1993 Ensenada: Sept-Oct

Sandrine Viscardi
Cardiac Intervention Nursing
Answer # 4 #

Myxomatosis affects the skin, eyes, genitals and liver. It is often fatal. It is common to see wild rabbits with myxomatosis during the spring and summer months.

Affected rabbits are often seen behaving abnormally. Sitting quietly by the side of the road or being out and about during the middle of the day, when normally they would be hiding in their burrows. You may see the characteristic swelling around the eyes and often affected rabbits appear to be blind. These rabbits are often easy to catch as they are so poorly.

In your own pet rabbits, you may not notice the earliest signs of myxomatosis. They are often subtle during the initial incubation period. The very first sign is often a skin lesion at the site of an insect bite where the virus starts to replicate. This very first bump or swelling in the skin is usually missed by even the most observant of rabbit keepers.

They become thickened and red with inflammation. You may notice that the eyes become infected with a discharge becoming apparent around this time. The eyes are sometimes described as looking “sleepy” in this initial stage.

Around this time you might also notice that your rabbit is not behaving as he or she normally would. They may become more withdrawn and less active or lethargic. A change in appetite is often noticed with your rabbit not wanting to eat or drink as much as normal.

At the same time, other lumps and bumps start to appear around the head. These swellings occur around the eyes, at the base of the ears, on the nose and lips and generally on the face. The head takes on a generally swollen and puffed up appearance giving the classic look of a rabbit with myxomatosis.

If you gently examine your rabbit underneath you will probably see a distinct swelling of the genitalia and anus. The signs of general lethargy and lack of appetite will also become more pronounced with your rabbit not wanting to eat or drink much at all. Other lumpy skin lesions can also become apparent anywhere on the body.

They have a swollen head and face. Their eyelids may become so swollen that they can no longer open them at all. This means that the rabbit becomes effectively blind. There may also be a nasty creamy discharge from the eyes and nose . Some of the skin lesions can start to ooze and become crusty.

A rabbit with fully developed myxomatosis may have difficulty breathing due to swellings around the nose. Pneumonia and other secondary diseases are common if a rabbit develops myxomatosis. As a result, they are at extreme risk of complications from other illnesses due to their weakened state. If a wild or unvaccinated rabbit has myxomatosis the prognosis is extremely poor and often euthanasia is often the kindest way to prevent suffering.

Over time, if a rabbit survives, the lumpy skin lesions can become hard and crusty. Eventually the lumps will dry out and drop off. These skin lesions usually leave scars, especially around the eyes and nose.

However, if a rabbit has been previously vaccinated against myxomatosis they may succumb to a more chronic but milder form of the disease. Skin lesions tend to be the major sign in this situation and these can lead to scarring if the rabbit survives.

In this atypical form of myxomatosis, the skin can show circular crusty lesions which can look quite red and raw. Eventually, these areas crust over and then drop off with the rabbit having a good chance of recovery. With this milder form of myxomatosis, your rabbit will still be very unwell and susceptible to secondary problems. So good veterinary care is still essential to give your pet the best chance of overcoming the disease.

As Myxomatosis is such a serious disease, vaccination is recommended to help reduce the severity of disease. It will also give your rabbit a better chance of survival if they do contract myxomatosis. However, since the vaccination is not 100% effective in preventing myxomatosis other precautions should also be taken.

These include ensuring that your pet rabbits are not in contact with wild rabbits. You may also use a rabbit-friendly product recommended by your vet to control fleas, which can carry the disease. Since mosquitos can also transmit myxomatosis when they bite, it will help to ensure that there is no stagnant water for mosquitoes to breed in around your rabbit’s environment. Also, use mosquito netting over the hutch if necessary.

Remember that if you do ever catch a wild rabbit that seems to have myxomatosis you should ideally wear gloves when you handle them. Then take them quickly to your local veterinary practice. If you have your own rabbits at home you should change your clothes and wash your hands thoroughly before handling your own pets again. You could carry the virus home on your hands or clothing. This will not be a problem for you but could harm your own rabbits.

Miku Forlani
Script Doctor